Device for casting iron and other difficultly-fusible metals under pressure



Dec. 1 I 1925. 1,563,523

E. PETERSSON DEVICE FORCASTINCT IRON AND OTHER DIFFICULT FUSIBLE METALSUNDER PRESSURE Filed Sept. 11. 1924 Patented Dec. 1, 1925.

UNITED STATES PATENT OFFICE.

ERNST PETERSSON, OF OREBRQ, SWEDEN.

DEVICE FOR CASTING IRON AND OTHER DIFFICULTLY-FUSIBLE METALS UNDERPRESSURE.

Application filed September 11, 1924. Seria1 1\T0. 737,196,

- To all 107mm it may concern:

Be it knownthat 1,.ERNS'1 Pnrnnsson, a subject of the King of Sweden,residing at Orebro, Sweden, have invented certain new and usefulImprovements in' Devices for Casting Iron and Other Difliculty-FusibleMetals Under Pressure, of which the following is a specification. 4 r

This invention relates to a device for easting iron and other difficultyfusible metals under pressure, and particularly when producing thepressure by vacuum. The objectof the invention is to provide a tightconnection between the molten'metal in a crucible and the mold duringthe casting operation.

The invention consists, chiefly, in this that a pipe consisting of anincombustible material, for instance, graphite or the like is providedin a crucible and extends from the bottom of said crucible or from theproximity thereof and outside the crucible above or at or substantiallyatthe rim of the crucible and through the melting furnace, and is atthis end provided with or formed as a nozzle which is forced at thecasting instant against the mold.

In the annexed drawing some forms of embodiment of a device according tothe invention are shown. Fig. 1 shows a crosssection of a meltingfurnace and a crucible according tothe invention placed therein. Fig. 2is a similar view, showing a somewhat modified form of embodiment of thecrucible. .Fig. 3 shows'a suitable arrange ment of the casting nozzle.Fig. 4 is an end view of the nozzle according to Fig. 3. Fig. 5 shows aheating and insulating device for the part ofthe pipe extending from thecrucible through the wall of the furnace.

Referring to Fig. 1, there is provided in the furnace 1 a crucible 2, inthe wall of which there is formed a channel 3 extend ing from the rim ofthey crucible to the bottom thereof. Inserted in said channel 3 is apipe 4 consisting of an incombustible material, such as for instance,graphite or the like, the lower'end of said pipe extending, as does thechannel 3, to the bottom of the crucible, while the upper end of thepipe is bent and extends through the wall of the furnace. The pipe 4forms at its outer end a nozzle 5 having a spherical shape and which ispressed at the casting instant against the mold. In' this case the inletof the mold ought to have a conical form, so that, when pressing themold against the nozzle 5, a tight connection is obtained between themold and the molten metal in the crucible '2 independent of the locationof the mold with relation to the nozzle. Obviously, this is of a greatimportance particularly in casting under pressure produced by vacuum inorder to prevent'tlie formation of air-holes in the castings. l

In the modification shown in Fig. 2 there is formed at the rim of thecrucible 2 from the material of the crucible proper a pipe 6, provided,as is the pipe 4 in the form of embodiment according to Fig. 1, withanozzle 5 having a sphericalshape, said nozzle extending outside thewall of the furnace.

-The said pipe 6 communicates directly with the channel 3 extending tothe'bottom of the crucible, so that a tight connection will be obtainedbetween the molten metal in the crucible 2 and the mold, when pressingthe latter against the nozzle 5x I Supposing the inlet of the moldtohave whereby'the adjustment of the mold ought to be such that the saidplane surfaces will be as parallel as possible. In order to compensatefor slight inaccuratenesses as to the said adjustment and in order toperform a uniform distribution of the pressure between the saidsurfaces, either the mold or,

as shown in Figs. 3 and 4, the nozzle 5 with the pipe 4 (6) and thecrucible 2 is according tothe invention suspended in a so-called Cardansuspension device 8, comprising a ring -11 surrounding the nozzle 5 andpivotally secured to said nozzle '5 by means of two diametricallyopposed gudgeons 12, said ring 11 being further, pivotally secured to afixed frame 13 or the furnace proper by -means of two furtherdiametrically opposed gudgeons 14 located at right angles to thegudgeons 12, so that the nozzle 5 with the pipe 4 (6) will be free toswing in any direction. The plane surface 7 of the nozzle 5 will, thus,while pressed against the mold, be automatically adjusted in parallelwith the corresponding plane surface of the mold, thus performing aneffective tightening between the said surfaces.

In order to prevent cooling of-the pipe 4; (6) at the place, where itpasses through the wall of the furnace, said pipe is, as apparent fromFig. 5, surrounded by a sleeve 9 consisting, preferably, of graphite andthe fore end of which bears tightly against the pipe at the nozzle 5 andthe interior of which is in communication with the melting chamber, soas to utilize the heat of radiation from said chamber. The said sleeve 9is surrounded by a second sleeve 10 having interior flanges bearingtightly against the sleeve 9, so that a closed airchamber will be formedbetween the said sleeves preventing the radiation of heat from thesleeve 9 and the pipe 4 (6). If

desired, a heating device of a known type, for instance an electricalheating device, may, obviously, be used for heating the part of saidpipe extending through the Wall of the furnace.

What I claimas new and desire to secure by Letters Patent of the UnitedStates of America is 1. In a device for casting iron and otherdifiicultly fusible metals by forcing the molten metal into the mold byvacuum, the combination of a furnace, a crucible located in saidfurnace, a pipe extending into the metal bath in the crucible andconsisting of an incombustible material and having a nozzle adapted tobe pressed, at the casting instant, against the mold, said nozzle havinga plane surface at the side to be pressed against the mold, and aself-adjusting suspension device carrying said nozzle and its pipe andpermitting the said plane surface of the nozzle, when pressed againstthe nozzle, to automatically adjust itself in alignment with the inletside of the mold,

so as to perform an air-tight connection between the nozzle and themold.

2. A device according to claim 1, characterized by the nozzle suspensiondevice comprising a ring hinged to the nozzle by means of twodiametrically opposed gudgeons and to a stationary part by means of twofurther diametrically opposed gudgeons, said latter gudgeons beinglocated at right angles to said first-mentioned gudgeons.

In testimony whereof I aifix my signature.

ERNST PETERS-SON.

